There is increasing interest in planar carbon forms, especially single and multi-walled carbon nanotubes. Carbon nanotubes were first synthesized by Ijima in 1991 using an arc-discharge reaction. Much of the focus of current studies focus is on thinly fabricated mono molecular sheets of carbon called graphene. These and other planar carbon forms are subjects of a great deal of interest, in particular owing to their mechanical strength, conductor or semi-conductor properties, and thermal properties.
Future commercial applications for these substances could be widespread and diverse, likely ranging from the electronics industry to health sciences and medicine. The manufacture and use of planar carbon forms, however, currently presents several unknowns including environmental impacts, the ability to sequester the product in a production facility, and the pharmacokinetics, pharmakodynamics, biodistribution, and toxicology of these materials in the body. Of particular interest is the biodistribution of planar carbon forms in an organism after accidental or therapeutic administration or exposure to planar carbon forms. Several in vitro studies suggest that the inhalation of carbon nanotubes can present a significant risk to the lungs. Similarly, in vivo studies suggest that carbon nanotubes may cause extensive inflammation in the lungs potentially leading to fibrosis. Moreover, functionalization of planar carbon forms and modifications to improve biocompatibility of these materials may actually increase the toxicity associated with these materials.
Unfortunately, studies of biodistribution, pharmakodynamics, etc., are difficult to perform and typically rely on extensive modifications of the base planar carbon form such as by extensive labeling that may lead to alteration of the actual properties of the carbon forms relative to that of planar carbon forms in their unmodified state. Thus, simple and directly labeled planar carbon forms and methods of their production are needed.